Sealing ribs for the suction boxes of paper machines



Sept. 13,' 1955 K. PLANER 2,717,540

SEALING RIBS FOR THE SUCTION BOXES OF PAPER MACHINES med Aug. 21, 1952 for United States SEALING RIBS FOR rI-IE SUCTlON BOXES GF PAPER MACHINES Karl Planer, Steyrermuhl, Austria Application August 21, 1952, Serial No. 305,596 4 Claims. (Cl. 92-51) a better seal such leather lined Wooden ribs were often arranged as floats in water filled grooves, the force of buoyance, caused by their floating in the water filled grooves, urging same against the forming wire (sieve) sliding on top. As the width of the forming wire is less than the length of the sealing ribs, perpendicularly arranged to the moving direction of the forming wife, the sealing ribs and/or their linings of leather and the like, are exposed to heavier wear along the distance contacted by the sliding forming wire, than at the two extremities of sealing ribs where higher, unworn sections remain. By means of a vibrating frame the forming wire is continuously shaken in a direction transversely to the travelling direction so that the unworn portions of the sealing ribs cannot help damaging the forming wire borders or rims. It has been suggested to use cylindrical rubber ribs, fixed by clamps, so that they can be turned according to wear. However, this is a complicated solution requiring a repeated adjustment and turning of the ribs. Finally, sealing ribs are known to be provided with a groove lled with a sealing liquid which however are qualified to only seal the suction space in case of suction rolls, whereby only walls can be sealed that are located in parallel relation to the travelling direction of the forming wire.

In contradistinction to the above the invention consists in the sealing rib being provided with a hollow space running through its entire length, said space being closed at either extremity of the sealing rib, an elastic covering being provided at the side of the forming wire, which is acted upon by a pressure medium such as Water under pressure, compressed air or the like, Whose pressure can be modified according to the requirements of operation. Owing to the possibility of altering the pressure it is possible, without having to tamper with the sealing rib, to adapt the pressure of the elastic covering to the forming wire as desired. On the areas on which the covering will have become thinner owing to wear, the pressure of the pressure medium will make itself felt more energetically than on the areas where the thickness of the covering has not been reduced so that the pressure and the adhesion of the elastic sealing ribs surface to the forming wire are always the same.

The drawing reveals the nature of the invention by way of different embodiments, Fig. 1 being a sealing rib in cross-section, and Figs. 2-4 represent three further embodiments of sealing ribs, likewise in cross-section. Fig. 5 is a cross-section through a suction box provided with the sealing ribs according to the invention, taken along the line V-V of Fig. 6, whereas Fig. 6 shows a longitudinal section through a portion of a suction box.

The suction box 7 is, in a manner known, provided atent O with the suction pipe 15 and the fastening ledges 6 for the sealing ribs. The sealing rib according to Fig. 1 is composed of a wooden rib 3 fixed to the fastening ledge 6 by means of screws 5 conveniently spaced. The sealing rib 3 which may also be made of metal or plastic material is provided with the groove 4 constituting the hollow space and extending along the entire length of the rib, said groove being open on top and being dovetailed along the longitudinal sides by way of relieving. The covering 1, made of rubber, leather, or elastic plastic material is-on the longitudinal sides-tted with lugs 2 and is pressed or cast under pressure, so that the lugs 2 will tightly and sealingly engage the dovetailed grooves of the rib 3 so as to hermetically close, in the upwards direction, the hollow space formed by the groove 4. Caps 11 are employed for closing the hollow space at the longitudinal ends of the rib. A feed line 12 for the pressure medium, passing through the suction box, conveys the pressure water, the compressed air, and the like into the hollow space. An adjustable pressure regulator or governor 13 permits of controlling the pressure of the water etc. in the hollow space. The pressure 0f the water etc. in the hollow space expands the elastic covering 1 over which the forming wire moves travelling, so that it is pressed upwards against said forming wire 10 warranting a perfect seal.

According to Fig. 2 the elastic body 1 grasps the rib 3, whereby the`ends 8 of the former are tighteningly fastened by means of wooden ledges and the like 9 e. g. by way of screwing to the rib 3. According to Fig. 3 the sealing body has the shape of a hose with a hollow space 4 and is tightly fastened by the lugs 2 engaging the dovetailed grooves of the rib 3. According to Fig. 4 the hose-like sealing body 1 surrounds the rib 3 on all sides, whereupon said rib is-after the sealing body has been placed over the samefixed by screws 5 from below to the fastening ledges 6.

I claim:

1. A sealing device for suction boxes of paper machines comprising a rib of rigid material provided with longitudinal grooves on the sides thereof, an elastic covering provided' with lugs of a shape to tightly engage the longitudinal grooves and form a dovetail connection with the rib, said sealing device having a hollow sealing space running along the entire length of the device, caps closing the ends of the hollow sealing space, a fluid pressure medium within the space and means for supplying said fluid pressure medium to said space.

2. A sealing device as defined in claim l wherein the hollow space and the pressure medium are located within the elastic covering.

3. A sealing device as set forth in claim 2, wherein the pressure sealing medium is compressed air.

4. A sealing device as defined in claim l, wherein the hollow space and the pressure sealing medium are located within the rigid rib.

References Cited in the file of this patent UNITED STATES PATENTS 1,353,941 Aitken Sept. 28, 1920 1,666,234 Cullen Apr. 17, 1928 1,677,128 Aldrich July 17, 1928 1,844,641 Wein Feb. 9, 1932 1,881,105 Vedder Oct. 4, 1932 2,578,551 Hornbostel Dec. l1, 1951 FOREIGN PATENTS 421,020 France Dec. 10, 1910 '298,671 Great Britain Oct. 15, 1928 288,574 Germany lan. 13 1930 

